Installing and Using PlantUML Plugin in IntelliJ IDEA for Quick UML Diagram Creation

What is PlantUML

PlantUML is an open‑source project that enables fast creation of UML diagrams using a simple textual language, rendering the graphics via the powerful Graphviz engine. The generated diagrams can be exported as PNG images or vector SVG files.

Advantages of PlantUML

Fully text‑based editing, no drag‑and‑drop controls needed.

Platform‑independent – works anywhere a PlantUML JAR is available.

Integrates with many editors and IDEs such as IntelliJ IDEA, Eclipse, and Notepad++.

Installing the PlantUML Plugin in IntelliJ IDEA

Open File → Settings → Plugins , search for “PlantUML”, locate the “PlantUML integration” plugin and install it.

Installing Graphviz on Windows

Download the installer from https://graphviz.gitlab.io/_pages/Download/windows/graphviz-2.38.msi and run it.

After installation, add the following environment variables:

Variable GRAPHVIZ_HOME = D:\WorkWare\Graphviz2.38

Append %GRAPHVIZ_HOME%\bin to the Path variable (separate multiple entries with a semicolon).

Set GRAPHVIZ_DOT = %GRAPHVIZ_HOME%\bin\dot.exe

Verify the configuration by opening a command prompt and running dot -version ; the version information should be displayed.

Configuring PlantUML in IntelliJ IDEA

Navigate to File → Settings → Other Settings → PlantUML and ensure the path to the Graphviz dot executable is correctly set.

Creating UML Diagrams with PlantUML

Create a new file with the .uml extension, write the PlantUML script, and the IDE will render the diagram in real time.

@startuml
Alice -> Bob: Authentication Request
Bob --> Alice: Authentication Response

Alice -> Bob: Another authentication Request
Alice <-- Bob: another authentication Response
@enduml

The rendered diagram appears beside the source file, allowing instant visual feedback.

Alternative: PlantUML Chrome Extension

If you prefer not to install Graphviz locally, you can use the “PlantUML Viewer” Chrome extension, which renders the diagrams directly in the browser from the textual description.